Fortune LiFePO4 battery

I was starting to build a solar powered off-grid power for cabin. I have already purchased the 6kw 24v AIMS inverter, which was going to be used with Trojan L-16 lead acid batteries. After watching Will’s videos I’m inspired to purchase (16) of the Fortune 100Ah 3.2v batteries instead.
I would plan on 8s2p configuration for 24v 200ah battery bank.
Is it correct that I need two 8S 24v bms rated for 100ah discharge (1 for each string) ?
I have not found many options for 24v bms with adequate discharge capacity.

Will I have problems using a 6 kw inverter with a 4800ah LiFePO4 battery bank?

As far as your bank running the inverter, it is not going to care as long as the correct voltage range is maintained. Your 16 fortunes will put you 5.12kw hours (3.2 x 100 x 16). So 5Kw for one hour is 1C discharge rate. In a pinch they will go above that 1C discharge and easily exceed the 6kw inverter's capability. Ideally though, you want to keep your bank discharge rate much lower if you want to get the maximum life span, and most LiFEPO4s I have seen recommend a 0.3C discharge. To translate that over to you inverter load will be 5.12kw times 0.3 which gives you 1536 watts of cozy battery use for a little over 3 hours. IMO it's better to have an oversize inverter that you can expand into, so just be careful with how much power you are drawing, not to go too far above that C rating, which you will have to refer to from Focus.

On the BMS question, try re-asking on the BMS forum. So many new things are happening with BMS that your question may have a different answer today than it would have six months ago.

Typically, battery packs in Series like an 8S requires an 8S BMS to be able to manage / balance each cell independently. You can parallel the cells and still use the 8S BMS because you are effectively showing one cell by pairing it. This saves on BMS but there is a trade off. One of the paired cells may bottom or top out before it's "partner" but the collective reading from them is what the BMS & Balancer will see, so you could end up with one cell @ 3V and one @ 4V which isn't really a good thing.

The quick math says 6000W ÷ 24VDC = 250A, but as those are Low Frequency Inverters that means it is capable of 18,000W surge or 750A surge. NOTE, with a 24VDC system, the "normal / common" cut off is 4000W Inverters, above that, it is more practical & serviceable to go with 48V.

Given the load potentials on the 24V base, I would NOT use paralleled cells, I would strongly urge going with strictly 8S with a 150A BMS per "Pack" and then wire the packs in Parallel. Not only does that offer a "Fail Safe" if one BMS shuts off for some reason, the other keeps going but is also better for balanced Discharge & Charging between the pair which also serves as a Load Split between them. Also by Paralleling properly, you can add more packs into the bank as your needs (and realities) kick in if your short. Given the size of Inverter, it seems your expecting serious loading so you will be looking for more battery at some point I think. 2X 24V/100AH isn't that much in the grand scheme. *Remember to fuse each pack.*

BMS Options are really varied. There is everything from simply, plug it in and it does it's thing BUT you can't monitor, adjust or tweak the settings (typically they don't balance & need an external balancer too). The next step up is a "Smart BMS" which has Bluetooth or a remote of some type which allows for configuration , management & tweaking and often have built in cell balancers too. Then there are the heavy use BMS' with external relays and / or other functions and capabilities. Currently, the most common ones people are going for is the Smart BMS with Bluetooth & Balancing as it's the best bang for buck for smaller systems. There are a few threads running on these types here.

Excellent doc from Victron on Battery Pack configurations:

Hope that helps
Steve